1. Field of the Invention
The present invention relates to a surface mounted power supply circuit apparatus which is used for printers and electronics and especially including a DC-DC converter, and a method for manufacturing it.
2. Description of Related Art
A plurality of DC power supplies are used for electronics such as personal computers, mobile phones, or printers. For example, a 24V and 5V power supply is required for a printer, and a power supply circuit including a DC—DC converter is often used. The power supply circuit is generally composed of electronic parts such as a wire-wound inductor, a condenser, a diode and a so-called pressure raising IC or the like, and these electronic parts are often mounted on upper and lower surfaces of a circuit substrate.
Recently, a great number of small and thinned electronics have been used and therefore it is under avoidable circumstance that a power supply circuit used for such thinned electronics is thinned.
However, conventionally, in the power supply circuit including the DC—DC converter, especially, a proposal for thinning positively the circuit has not been carried out. A proposal for enabling the power supply circuit to surface-mount on the circuit substrate by improving a cost performance in manufacturing an assembly in which the power supply circuit is mounted on the circuit substrate has also not been accomplished.
Moreover, it is requested strongly that electronic parts manufactured in the future can be surface-mounted on a mother board which is an applied product to which the electronic parts are attached, in order to promote rationalization of manufacturing.